Electronic control system for gyroscopic stabilized vehicle

ABSTRACT

Embodiments of the invention describe receiving vehicle information data from a plurality of sensors. Said vehicle information data may indicate at least orientation of a frame of a vehicle, orientation of a front wheel of the vehicle with respect to the frame, orientation and rotational speed of a flywheel included in a gyroscope coupled to the frame, and speed of frame. 
     Based on said received data, a vehicle state may be determined. Based at least on this determination, at least one of the orientation and rotational speed of the flywheel may be adjusted. Said adjustment may be further based on an input to change at least one of speed and direction of the vehicle.

CLAIM OF PRIORITY

This application claims priority to Provisional Application No.61/314,540 filed on Mar. 16, 2010.

FIELD OF THE INVENTION

Embodiments of the invention relate to transportation vehicles, and moreparticularly to electronic systems to control gyroscopic stabilizedvehicles.

BACKGROUND

Rising energy costs and the impact of greenhouse gases on theenvironment have created a growing need for high efficiency vehicleswith a low carbon footprint. Inline-wheeled vehicles, such asmotorcycles and scooters, offer higher efficiency than conventionalfour-wheeled cars; however, this efficiency is mainly due to thephysical differences between inline-wheeled vehicles and four wheeledcars—e.g., reduced weight, fewer friction surfaces, and reduced drag.Furthermore, many users are unwilling or unable to operate motorcyclesand scooters due to the exposure to weather and wind, safety concerns inthe event of crashes, and the skills required to maintain vehiclestability during vehicle use.

Solutions to reduce inline-vehicle user exposure to weather and windhave typically been limited to devices partially shielding the driverfrom the elements (e.g., a windshield) in order to allow the user to usehis feet to help stabilize the vehicle during low-speeds. Furthermore,while there have been some solutions to attempt the build an encloseduser cabin for an inline-wheeled vehicle, these solutions either requireadditional (though smaller) wheels to stabilize the vehicle or do notprovide for vehicle stability during all potential and foreseeable uses.Prior art solutions that attempt to electronically stabilize aninline-wheeled vehicle have also failed to provide for resource andenergy efficient solutions to maximize the overall efficiency of thevehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description includes discussion of figures havingillustrations given by way of example of implementations of embodimentsof the invention. The drawings should be understood by way of example,and not by way of limitation. As used herein, references to one or more“embodiments” are to be understood as describing a particular feature,structure, or characteristic included in at least one implementation ofthe invention. Thus, phrases such as “in one embodiment” or “In analternate embodiment” appearing herein describe various embodiments andimplementations of the invention, and do not necessarily all refer tothe same embodiment. However, they are also not necessarily mutuallyexclusive.

FIG. 1 shows a partial cutaway side view of a vehicle includingembodiments of the invention.

FIG. 2 shows an exploded view of a flywheel assembly.

FIGS. 3 a-h show partial cutaway side views of vehicle in differentstates, indicating energy flows according to an embodiment of theinvention.

FIG. 4 shows an energy flow diagram according to an embodiment of theinvention.

FIG. 5 shows a flow diagram of a control system according to anembodiment of the invention.

FIG. 6 shows an embodiment of a control system.

Descriptions of certain details and implementations follow, including adescription of the figures, which may depict some or all of theembodiments described below, as well as discussing other potentialembodiments or implementations of the inventive concepts presentedherein. An overview of embodiments of the invention is provided below,followed by a more detailed description with reference to the drawings.

DETAILED DESCRIPTION

The basic concept of using gyroscopes to maintain a two-wheeled vehicleupright by using flywheel precession to generate counter-torque is known(while reference is made to gyro-stabilized two-wheeled vehicles in thisSpecification, the principles of gyro-stabilization may also be used inany vehicles which have a narrow track width such thatgyro-stabilization is used to stabilize the vehicle or to augment theirsuspension system in providing stability); however, such systems havenot become common for a variety of reasons, including the lack of adesign for a suitable control system for a vehicle to operate safely athighway speeds and in all conditions.

Previous attempts to incorporate flywheel stabilization added greatcomplexity and therefore weight to the vehicles due to the additionalmechanical drive-trains, power and fuel (or battery) requirements.Additionally, the flywheels themselves consumed a non-trivial amount ofenergy and so negated the inherent efficiency advantages of thetwo-wheeled vehicle itself. However, advances in electric drive systemsutilizing motor-generators allow for zero emission power for a vehicle,and provide the ability to use regenerative braking principles torecover greater amounts of energy when slowing down the vehicle. This,combined with advancements in energy storage density, allow for anextended range even with additional power used for gyro-stabilization.

The basic equations governing these effects are known and described byequations. The moment of inertia (I) for a solid disk is given byI=¼*m*r², with m being the mass of the disk and r being the radius. Fora given vehicle weight and center of gravity (CG), a gyro stabilizerflywheel may be sized so that the vehicle's vertical stability may becontrolled indefinitely while stopped. The radius, the mass, and thegeometry of the flywheel may be selected to maintain both a compact sizewhich can fit within the vehicle frame and still be able to provide aneffective moment of inertia I.

Causing a rotating flywheel to precess about an axis which is normal tothe flywheel axis of rotation will create a counter-torque orthogonal toboth the axis of rotation and the axis of precession. The usefulcounter-torque τ of a gimbaled flywheel assembly is given by theequation: τ=I_(disk)*ω_(disk)*ω_(axis). The rotational velocity of theflywheel plays a large role in the amount of useful torque τ availableto stabilize the vehicle. As one of the only controllable variables inthe governing equation for a selected flywheel mass and geometry,flywheel rotational velocity can be controlled to compensate for thevarying static load and load distribution of the vehicle andconsequently the correctional ability of a gyro stabilizer.

Additional variables used in the control of the vehicle include:

θ_(Vehicle) is the tilt of the vehicle from side to side measured inradiansV_(Vehicle) is the velocity of the vehicle as it moves down the roadmeasured in meters per secondω_(disk) is the rotational velocity of the flywheel measured in radiansper secondφ_(axis) is the tilt of the flywheel from vertical, measured in radiansω_(axis) is the rotational velocity of the tilt of the flywheel,measured in radians per secondθ_(steering) is the steering input, measured in radians

Using inputs θ_(Vehicle), V_(Vehicle), ω_(Flywheel), ω_(axis), φ_(axis),and θ_(steering), the θ_(vehicle) can be controlled by changingω_(axis), which outputs a torque orthogonal to φ_(axis) so as to opposeor increase changes to θ_(Vehicle). As φ_(axis) approaches 90° or n/2radians, the gyro's effectiveness in changing θ_(Vehicle) decreasesbecause the torque output is orthogonal to φ_(axis). The control ofφ_(axis) and θ_(Vehicle) by actuating ω_(axis) can be accomplished byusing a modern control system including major and minor loop control orstate space. Consequently, two outputs, φ_(axis) and θ_(Vehicle) may beaccounted for at the same time with priority going to ensuringθ_(Vehicle) is stable.

Flywheel geometry and material and precession motor sizing (whichdetermines the correctional ability of the gyro system) may depend onvariables such as: the vehicle weight and center of gravity atanticipated load conditions, maximum vehicle speed, maximum turn rate,and anticipated environmental conditions (e.g. cross winds, variationsin road gradients, & etc.). In one embodiment, the physical size andmass of the gyro assembly may be as small as possible for packaging andefficiency purposes. Embodiments of the invention may further beutilized by two wheeled vehicles substantially narrower than atraditional car or truck which therefore abides by motorcycle laws. Theflywheel mass is selected such that when rotating in the desired speedrange, a single flywheel may be capable of correcting an unstable stateof the overall vehicle and its contents for an extended period of time.Flywheel material selection is driven primarily by the tradeoffs betweenmaterial density (δ), material strength, energy storage ability andoverall weight. Energy storage (E) is related to moment of inertia andvelocity-squared by the equation:

$E_{disk} = {\frac{1}{2}*I_{disk}*{\omega_{disk}^{2}.}}$

Higher density material may allow for a smaller overall package, butgreater flywheel mass requires larger drive motors and hence greaterweight and space requirements.

Additionally, a flywheel with great mass may either be less responsiveto acceleration requests (i.e. spinning up to a given speed will takelonger) or may require a much larger drive motor to accelerate theflywheel within a given time. The flywheel mass may be optimized toincrease efficiency of the vehicle, and minimizing the gyro mass helpsto keep the overall vehicle mass lower, which means less energyconsumption in operating the vehicle. In one embodiment, the flywheelmaterials are carbon fiber or Kevlar, selected for their high tensilestrength for their weight, allowing higher rotation speeds (i.e. greaterthan 10,000 rpm) and more responsive acceleration. Higher densitymaterials such as steel, brass, bronze, lead and depleted uranium mayalso be used; however it is understood that the tensile strength ofthese materials does not allow for higher rotational speeds which limitstheir usefulness in minimizing the size and mass of the flywheel.

Based on the geometry of the disc, the moment of inertia can range from¼*m_(disk)*r_(disk) ² to ½*m_(disk)*r_(disk) ². Because the amount oftorque output by the precessing gyro is given byτ=I_(disk)*ω_(disk)*ω_(axis) increasing the I_(disk) with the otherinputs held constant means a greater τ. Therefore τ may be maximized fora given size and weight constraint to keep the vehicle usable andefficient. However, I_(disk) and ω_(disk) are related because asI_(disk) increases, the motor spinning the gyro needs to become morepowerful to achieve the desired ω_(disk) in an acceptable amount oftime.

The Output Torque (τ) of the gyro assembly in the X-direction alsodepends on the Angular Position of the gyro (φ_(axis)). Output Torque(τ) is maximized when the gyro's rotation is pointed vertically down orup. As the ω_(axis) increases, the gyro disc's rotation direction willmove faster towards or away from vertical. If the vehicle needs to bestabilized for a longer period of time, the ω_(axis) may be minimized tomaximize the amount of time that an acceptable Output Torque (τ) isproduced.

When the vehicle is coming to a stop and has low forward velocity (andtherefore low rotation speed of the wheels), the torque in the forwarddirection exerted by the lean of the vehicle is described by theequation M_(x)=r*f*Sin(θ_(Vehicle)), where r is the height of the centerof gravity for the vehicle, f is the force of gravity on the vehicle,and θ_(vehicle) is the amount of lean from vertical. The moment exertedby the precession of a flywheel is described by the equationM_(x)=I_(disk)*ω_(disk)*ω_(axis)*Sin(θ_(diskaxis)). For a nominal 500 kgvehicle moving at low speeds, the moment exerted by a vehicle with acenter of gravity 0.75 m above the ground and tipping 30 degrees fromvertical is 1131 N-m. To keep the vehicle stable would therefore require1131 N-m of counter-torque, but to move the vehicle upright, an excessof counter-torque may be required. In order to counter that tippingmotion, a moment M_(x) may need to be introduced by precessing the gyrostabilizer flywheel. If multiple flywheels are utilized, their momentsare additive.

A lean of 30 degrees is more than one would deal with in real worldsituations not involving a failure of the stability system, so aflywheel disk approximately of 7 kg with a radius of 0.15 m and a momentinertia of 0.070 kg-m-m, spinning at 1570 rad/s, and precessing at 10.47rad/s, with its axis vertical should exert a moment of 1295 N-m. In oneembodiment, two identical flywheels are used, spinning in oppositedirections and precessing in opposite directions so that the moment isexerted in the same direction, but the yaw moment M_(z) of the twoflywheels together would equal zero. The flywheels may each be sizedsuch that in the case of the failure of one flywheel, the remainingflywheel is able to stabilize the vehicle in most situations. Therefore,for the nominal 500 kg vehicle under the conditions described above,having a rolling moment of 1131 N-m, two flywheels would produce 2590N-m of counter-torque which would be sufficient to maintain or correctthe lean of the vehicle, and in the event of a partial failure of oneflywheel the remaining flywheel could provide sufficient correctionalmoment to control the vehicle to place it in a safe condition. Theflywheels may also be of equal size, or differing sizes.

Thus, it is to be understood that, at least in light of the abovedescription and the figures below, embodiments of the invention describean apparatus and methods to receive, via a plurality of sensors, data toindicate information describing a vehicle state. This information mayinclude, but is not limited to, orientation of the vehicle frame,orientation of a front wheel of the vehicle with respect to the frame,orientation and rotational speed of gyroscope flywheels included in thevehicle (i.e., gyroscopes coupled to the vehicle frame), and the currentspeed of the vehicle. Said gyroscopes may be aligned lengthwise withrespect to the front and rear wheel of the vehicle, widthwise withrespect to the frame of the vehicle (e.g., side-by-side), or heightwisewith respect to the frame of the vehicle (e.g., stacked).

Based at least in part on data received from said sensors, theorientation or the rotational speed of (at least) one of the flywheelsmay be adjusted. Embodiments of the invention may further adjust theorientation or the rotational speed of (at least) one of the flywheelsfurther based on an input to change the speed (e.g., acceleration orbrake input) or direction (e.g., steering wheel input) of the vehicle.For example, embodiments of the invention may cause the rotational speedof one of the flywheels to be reduced when an acceleration input isdetected, or cause the rotational speed of one of the flywheels to beincreased when a brake input (i.e., an input to engage a front or rearwheel brake) is detected; if it is determined the vehicle will execute aturn (i.e., the orientation of the front wheel with respect to the frameis detected), embodiments of the invention may adjust the orientation orthe rotational speed of at least one of the flywheels to maintainstability during the turn.

Using gyro stabilizer flywheels to receive and transfer energy back intoa drive system provides the advantages of a lighter weight and moreefficient two-wheel vehicle which can include an all weather interiorcabin having recumbent seating, with the high energy efficiency of aregenerative braking system and zero emissions propulsion. Transferringenergy between the flywheels motor(s)/generator(s) and the drive wheelmotor(s)/generator(s) through the energy storage unit during vehicle'sacceleration and deceleration maintains up to 95% energy efficiency andvehicle stability, thereby substantially increasing the range of thevehicle. A gyro stabilized vehicle without this power transfer systemmay be significantly handicapped due to the increased power requirementsof the gyro stabilizer compared to a conventional non-stabilizedvehicle.

Lower speed urban travel is generally the most energy intensive regimefor traditional vehicles, due to the energy lost in frequent braking andacceleration (both from the energy input into the brakes, and the energyused to accelerate the vehicle that is lost to subsequent braking).Therefore, it is to be understood that a great leap in energy efficiencymay be achieved by providing a gyro-stabilized vehicle that can travelon two-wheels, accommodate recumbent passenger arrangements, provide thesafety of an all-weather enclosed passenger cabin, provide drivingcontrols similar to a conventional car, and which can greatly improvethe range and efficiency of a gyro-stabilized vehicle by integrating thestabilizing flywheels into a regenerative braking system.

At lower speeds, such as when the vehicle is accelerating from a stop orslowing to a stop, or at speeds common in urban areas and stop-and-gotraffic situations, the self stabilization properties of the vehicle arenot sufficient to maintain the upright orientation of the vehicle.Consequently, in the prior art much more skill is required from therider to operate the unstabilized vehicle, and the rider may be requiredto use his or her own physical strength to balance the vehicle at a stopdiminishing the utility and equal accessibility.

Gyro-stabilization at low speeds and at stop also presents a simplercontrol problem than that encountered at higher speeds. A gyrostabilizer may be mounted to a vehicle through gimbal mountings,utilizing the gimbal motors to precess the gyros to createcounter-torque against vehicle roll moment. Vehicle state can bemeasured by inertial and absolute position sensors mounted to thevehicle which can then be used to determine the amount and rate ofprecession required to provide sufficient counter-torque to maintain thevehicle upright. Generally, the restorative ability of the gyrostabilizer may be able to stabilize a vehicle with a passenger for asufficient amount of time such as may be encountered at a stop light orstop sign. In one embodiment, when the vehicle is stopped for prolongedperiods or turned off, the vehicle may support itself by anautomatically deployed mechanical support.

In one embodiment, the gyro stabilizer flywheel(s) and drive wheel(s)are coupled to their own respective motor-generator(s) which can operatein a motor-mode to drive their respective loads, or switch to agenerator-mode to slow the rotating loads and harvest this energy fortransfer to other loads. The electrical power system includes an energystorage unit to provide temporary storage of electrical energy whiletransferring it between the drive/braking system and the gyro stabilizerflywheels or for longer durations of time such as when the vehicle ispowered off.

A system controller receives sensor data from the vehicle's statesensors (inertial and absolute), the gyro stabilizer's state sensors,and other parameters to control the amount and timing of correctionaltorque imparted by the gyro stabilizer.

A gyro stabilizer includes at least one actively gimbaled flywheelcoupled to a vehicle. In one embodiment, a gyro stabilizer includesfirst and second counter-rotating flywheels which are independentlygimbaled. Each flywheel may be mounted with a vertical axis of rotationin a neutral position and with the gimbal axes parallel to each other.In this embodiment, the counter-rotating flywheels are precessed inopposite directions, such that their counter-torque is additive, buttheir yaw effects on the vehicle cancel each other.

Use of two flywheels also allows each individual flywheel to be mademore compact in order to fit within the narrow frame of the vehicle.Additionally, in the event one flywheel fails, the second flywheel canbe used to provide adequate stability during an emergency stop of thevehicle to place it in a safe condition. In the case of either flywheelfailure or emergency balance situation, a failsafe protocol engaging thedeployment to the mechanical landing gear may be used to keep thevehicle upright and maintain the driver's safety.

Referring to FIGS. 1-6, embodiments of the invention comprising aregenerative-powered gyroscopic stabilization apparatus are showninstalled in inline two-wheeled vehicle 100. In this embodiment, vehicle100 comprises vehicle frame 110, vehicle body 120 enclosing vehicleinterior 130 and access door 140 which rotates open about a hingemechanism 150. Recumbent operator's seat 160 may be provided withdriving controls including steering unit 170, accelerator 180 and brake190. In this embodiment, said driving controls are arranged in thefamiliar layout of conventional automobiles having steering wheels andpedals.

In this embodiment, vehicle 100 further includes first and second drivewheels 200 and 210 respectively. First and second drive wheels motorgenerators 220 and 230 are coupled to drive wheels 200 and 210,respectively, through drive chains 240 and 250, respectively.

In this embodiment, gyro stabilizer 260 is coupled to vehicle 100through vehicle frame 110. Gyro stabilizer 260 may include first andsecond gyro assemblies housing flywheels 270 a and 270 b (said gyroassemblies similar to assembly 260 a), which in this embodiment areessentially identical. It is to be understood that in other embodiments,the first and second gyro assemblies/flywheels may differ in size andmaterial composition.

First gyro assembly 260 a, as shown in FIG. 2, includes flywheel 270 a,flywheel motor-generator 280 a coupled to flywheel 270 a, gimbal 290 acoupled to flywheel 270 a, and precession motor 300 a having driveportion 310 a coupled to gimbal 290 a and frame portion 320 a coupled tovehicle 100. In this embodiment, precession motor-generator frameportion 320 a is coupled to vehicle 100 through mounting bracket 330 a,which is fixedly mounted to vehicle frame 110.

Flywheel 270 a is contained within a gyro housing having a bottomportion 340 a and top portion 350 a, which in this embodiment areassembled using threaded fasteners 360 a and alignment pins 370 a. Gyrohosing top portion 350 a includes gimbal 290 a, which provides theprecession axis for precessing the gyro assembly to create thecounter-torque that may maintain stability for vehicle 100, as well as abearing housing 380 a to support flywheel 270 a. Motor-generator mountbolts 390 a and flywheel mount bolts 400 a are provided to coupleflywheel motor-generator 280 a, flywheel 270 a and the gyro housing. Inthis embodiment, flywheel 270 a and flywheel motor-generator 280 a areboth contained within gyro upper and lower housing portions 340 a and350 a, for ease of maintenance and protection. Gyro stabilizer 260 maytheoretically be located anywhere on the vehicle so long is it can becoupled to the vehicle frame 110 in order to transmit the counter-torqueof the first and second precession motors (e.g., motor 300 a) to vehicleframe 110. In this embodiment, gyro stabilizer 260 is locatedapproximately at the anticipated vertical and fore-aft center of gravity(“CG”) of vehicle 100 at standard conditions.

Referring to FIGS. 1, 3 a-h and 4, energy storage unit 410 is providedincluding battery bank 420, capacitor bank 430, and a power switchingcircuit in electrical communication with battery bank 420, capacitorbank 430, first and second drive wheel motor-generators 220 and 230, andwith first and second flywheel motor-generators 270 a & b. In oneembodiment, battery bank 420 includes battery cells located in locationsdistributed along vehicle frame 110 so as to distribute the weight andfit within the frame of the vehicle. Battery bank 420 may be charged byplugging into a charging station or electrical wall outlet at a parkingspace or garage, or one or more battery cells may be physicallyexchanged to provide a fresh charge.

Referring to FIGS. 1, 3 a-h, 5 and 6, a control system including aplurality of sensors producing electronic signals is illustrated. Saidplurality of sensors may indicate at least the absolute state andinertial state of vehicle 100 and gyro stabilizer 260. This examplecontrol system further includes system controller 440 in electroniccommunication (via any communication means known in the art) with theplurality of sensors, first and second drive wheel motor-generators 220and 230, first and second flywheel motor-generators 280 a & b, energystorage unit 410, accelerator 180, brake 190 and steering unit 170. Inthis embodiment, the plurality of sensors comprises Flywheel StateSensors 560 coupled to each flywheel, Vehicle Inertial State Sensors570, Vehicle Absolute State Sensors 580, and Vehicle State Sensors 590.The plurality of sensors include at least three-axis orientation sensor450 coupled to vehicle frame 110 providing data indicating vehiclerotation and angle, accelerometer 460 coupled to vehicle frame 110providing data indicating vehicle linear acceleration, first and seconddrive wheel speed sensors 470 and 480, and vehicle tilt sensor 490. Inthis embodiment, tilt sensor 490 includes a left-side and right-sideinfrared laser which measures distance to ground from a fixed point onvehicle 100, thus providing a control input for in situ calibrating oforientation sensor 450 and safety backup for orientation sensor 450.System controller 440 receives data from the plurality of sensorsindicating one or more of first and second flywheel tilt angle, tiltvelocity (i.e. the rate at which precession motors 300 a & b arerotating flywheels 270 a & b about their respective gimbals), flywheeldisc velocity (i.e. the rotational velocity of flywheels 270 a & b).Compass and Global Position System (GPS) sensors may also be provided.

Referring to FIGS. 5 and 6, system controller 440 receives inputs fromthe plurality of sensors, uses these inputs to determine the actualorientation and state of vehicle 100, and transmits control signals toprecession motors 300 a & b to rotationally accelerate their driveshafts (i.e. to induce precession of flywheels 270 a & b about gimbals290 a & b), thereby creating a counter-torque that is transmitted tovehicle frame 110 to maintain a desired vehicle angle. Processors550-553 are in electronic communication with sensors indicating thestates of various components and vehicle 100 as a whole. In oneembodiment, electronic filters 505 a-d are interposed to reduce systemnoise and amplify sensor outputs for use by the processors. Althoughdescribed as separate “processors” for illustrative purposes, it is tobe understood that processors 550-553 may actually comprise fewer orgreater than the four physical computer processors/cores shown.

In one embodiment, Inertial Sensors 570 are packaged and processed in aclosed module such that the output is the vehicle's inertial state. Thisinertial state may be calibrated with absolute sensors 480 and 490mounted on the exterior of vehicle 100 to account for inaccuracies inthe inertial sensor measurements.

Gyro State Processor 550 may receive inputs from Flywheel State Sensors560 coupled to each flywheel. Said Flywheel State Sensors producesignals indicating important measurements including flywheel tilt anglerelative to the vehicle frame, flywheel tilt velocity (i.e. therotational velocity at which the precession motor is rotating theflywheel about its precession axis), and the disk velocity (i.e. therotation speed of the flywheel disk about its axis of rotation). In oneembodiment, Gyro State Processor 550 uses this information to determinethe actual instantaneous magnitude and direction of the moment exertedby gyro stabilizers 260 a & b on vehicle 100, determine the health ofsystem components, and provide for internal optimization to allow forextended use of the gyro stabilization system (i.e., Gyro State 555).

In one embodiment, Vehicle State Processor 551 receives inputs from oneor more of Vehicle Inertial State Sensors 570, the Vehicle AbsoluteState Sensors 580, and Vehicle State Sensors 590 to determine VehicleState 556. Said Inertial State Sensors may produce electronic signalsindicating the rotational and linear acceleration, velocity, andposition of vehicle 100. Said Absolute State Sensors may produceelectronic signals indicating the vehicle tilt angle direction andmagnitude, as well as vehicle direction of travel, speed over ground andabsolute geographic position provided by sensors including an electroniccompass and GPS receiver. Said Vehicle State Sensors may produceelectronic signals indicating drive wheel speed (i.e. rotational speedof each of the drive wheels 200 and 210), the brake status (i.e. therate of decrease of the vehicle drive wheel 200 and 210 rotationalspeeds), user inputs to the vehicle through the accelerator 180 andbrake 190, and the steering sensor providing the ordered turn radius ofthe vehicle through steering unit 170. It is to be understood that saiduser inputs may comprise input from a driver, a computer program, etc.

Vehicle State Processor 551 may determine the vehicle's proper tiltangle 610 for the current conditions and compares this to the vehicle'scurrent tilt angle 620 (including roll movement 630) to determine theVehicle Tilt Error 640. Said Vehicle Tilt Error may be used by 553 GyroControl Processor to determine the required precession axis input toproduce sufficient counter-torque 650 to return to or maintain vehicle100 within desired tilt range 610.

Thus, it is to be understood that, at least in light of the abovedescription and the respective figures, embodiments of the inventiondescribe a vehicle including a processor, a memory, and a control module(or logic) to adjust the orientation or the rotational speed of agyroscope flywheel based, at least in part, on the current or intendedvehicle state. Said vehicle state may be determined by data receivedfrom a plurality of sensors included in the vehicle. Said sensors maydetect the orientation of the vehicle frame (e.g., tilt angle of theframe), the orientation of the front wheel with respect to the frame,the orientation and rotational speed of the gyroscope flywheel, and thespeed of the vehicle.

The control module may further receive input to change the speed or thedirection of the vehicle, and adjust the orientation or the rotationalspeed of the flywheel further based, at least in part, on said receivedinput. The control module may also determine an intended vehicle statebased, at least in part, on the received input, and adjust theorientation or the rotational speed of the flywheel further based, atleast in part, on said intended vehicle state. For example, if thereceived input comprises a command to turn the front wheel, the intendedvehicle state may be determined to be a turn, and the control module mayadjust the orientation or the rotational speed of the flywheel tomaintain vehicle stability during the turn.

Embodiments of the invention may further include a power storage unit asshown in FIGS. 3 a-h and FIG. 4. In one embodiment, power storage unit410 includes battery bank 420, storage capacitor bank 430, and switchingcircuitry, which supply power as well as provide a mechanism for storingand transferring power from rotating components throughmotor-generators. The electrical current produced through regenerativebraking may exceed the ability of the battery bank 420 to absorb energywithout damage. It is understood that capacitors are better able tohandle such large surges, so in one embodiment the battery bank 420 isselectively placed in parallel electrical communication with the storagecapacitor bank 430 and motor-generators 220, 230, and 280 a & b, havinga common system electrical ground, through power switching circuits. Inthis way storage capacitor bank 430 acts as an electrical buffer fortemporarily storing power surges from system components which exceed thebattery capacities, and distributing this stored power either directlyto motorized components or by charging the battery bank.

Power storage unit 410, in electrical communication with flywheelmotor-generators 280 a & b and drive wheel motor-generators 220 and 230,may be used to provide power to vehicle 100, and to transfer energybetween flywheels 270 a & b and drive wheels 200 and 210 using amotor-generator system. Motor-generators 280 a & b and 220 & 230 may becoupled to flywheels 270 a & b or to drive wheels 200 & 210,respectively, by mechanical, hydraulic, electromagnetic or othersuitable coupling mechanisms known in the art.

At low vehicle speeds gyro stabilizer flywheels 270 a & b may rotate ata high speed in order to provide sufficient inertial moment duringprecession to maintain vehicle stability. As vehicle 100 increasesspeed, less inertial moment may be required from gyro stabilizerflywheels 270 a & b to maintain vehicle stability, so flywheels 270 a &b are spun down (to a low speed or allowed to come to a halt). Thisenergy may be recovered and transferred to first and second drive wheelmotor-generators 220 and 230 for propulsion. Similarly, when vehicle 100slows down via engagement of the braking system, energy used to brakedvehicle 100 may recovered and transferred to gyro stabilizer flywheels270 a & b to spin them up to higher rotation speeds to provide stabilityto vehicle 100 as first and second drive wheels 200 and 210 slow down.Lines A1, A2, B1, B2, C1 and C2, with arrows, illustrate the primaryenergy flow paths and directions during the above conditions. When linesA1 and A2 are illustrated in a clockwise direction, this illustrationrepresents that the drive motor-generators 220 and 230 are in a motormode, and similarly counterclockwise represents a generator mode.

In FIG. 3 a, vehicle 100 is shown cruising at a speed of approximately55 mph (90 kph). In this embodiment, flywheels 270 a & b are at very lowrotational velocity, essentially at idle speed. Electrical current isflowing from the energy storage unit battery bank 420 to the first andsecond drive wheel motor-generators 220 and 230, which are operating inthe motor mode.

In FIG. 3 b, vehicle 100 is ordered to slow to approximately 35 mph (56kph). In this embodiment, system controller 440 receives the brake input(from an operator or from an automated signal) causing first and seconddrive wheel motor-generators 220 and 230 to switch to the generator modethereby generating electrical current, and first and second flywheelmotor-generators 280 a & b to switch to the motor mode, thereby drawingelectrical current and spinning up first and second flywheels 270 a & bto a low rotational velocity. System controller 440 causes the powerswitching circuit to direct the generated current through the capacitorbank to the first and second flywheel motor-generators. First and secondflywheels 270 a & b may be spun up only to low speed (if at all) if therotation velocity of first and second drive wheels 200 and 210 stillcontributes significantly to vehicle stability, so only a relativelysmall amount of additional counter-torque is required from gyrostabilization units 260 a & b.

In FIG. 3 c, vehicle 100 is ordered to slow from 35 mph (56 kph) toapproximately 15 mph (24 kph). System controller 440 receives the brakeinput and causes first and second drive wheel motor-generators 220 and230 to switch to the generator mode (or remain in the generator mode)thereby generating electrical current, and first and second flywheelmotor-generators 280 a & b to switch to (or remain in) the motor mode,thereby drawing electrical current and spinning up first and secondflywheels 270 a & b to a mid-range rotation speed. System controller 440causes the power switching circuit to direct the generated currentthrough capacitor bank 430 to first and second flywheel motor-generators280 a & b. In this embodiment, first and second flywheels 270 a & b spinup to mid-range rotation speed as the low rotation speed of first andsecond drive wheels 200 and 210 is not sufficient to maintain vehiclestability.

In FIG. 3 d, vehicle 100 is stopped. System controller 440 causes firstand second flywheels 270 a & b to increase to high rotational speed(approximately 10,000 rpm in this embodiment, herein referred to as“hover speed”), because vehicle stability is entirely dependent oncounter-torque generated by precessing gyro stabilization units 260 a &b. First and second flywheel motor-generators 280 a & b are in the motormode and draw electrical current from energy storage unit 410; in oneembodiment, current is drawn initially from capacitor bank 430 until thecapacitor bank's charge dissipates to a predetermined level, and thenfrom battery bank 420.

In FIG. 3 e, vehicle 100 drives away from stop. In this embodiment,system controller 440 causes drive wheel motor-generators 220 and 230 toswitch to the motor mode to accelerate the vehicle, and causes flywheelmotor-generators 280 a & b to switch to the generator mode to slow downflywheels 270 a & b. As vehicle 100 accelerates and the rotating drivewheels 200 and 210 contribute more to vehicle stability, first andsecond flywheels 270 a & b are permitted to spin down with theirmotor-generators in the generator mode. System controller 440 causes thepower switching circuit to direct the current generated by flywheelmotor-generators 280 a & b during spin down to drive wheelmotor-generators 220 and 230. If vehicle 100 does not accelerate to asufficient velocity to contribute significantly to vehicle stability,then flywheels 270 a & b may continue to rotate at high speed andcontinue to draw current from power storage unit 410.

In FIG. 3 f, vehicle 100 continues to accelerate to approximately 15 mph(24 kph). In this embodiment, system controller 440 maintains drivewheel motor-generators 220 and 230 in the motor mode to acceleratevehicle 100, and maintains flywheel motor generators 280 a & b in thegenerator mode to continue to spin down flywheels 270 a & b. As vehicle100 accelerates and starts to maintain its own stability, first andsecond flywheels 270 a & b are permitted to spin down with theirmotor-generators 280 a & b in the generator mode. System controller 440causes the power switching circuit to direct the current generated byflywheel motor-generators 280 a & b during spin down to drive wheelmotor-generators 220 and 230 via capacitor bank 430.

In FIG. 3 g, vehicle 100 continues to accelerate to approximately 35 mph(56 kph). In this embodiment, first and second flywheels 270 a & bcontinue to spin down to low rotation speed and are maintained at thislow speed until an ordered vehicle speed change requires a differentflywheel rotational speed. System controller 440 causes the powerswitching circuit to align battery bank 420 in parallel with capacitorbank 430, such that battery bank 420 may provide the primary power fordrive wheels 200 and 210.

In FIG. 3 h, vehicle 100 is shown in parking mode or long-term stop.Mechanical support mechanism 500 (herein referred to as “landing gear”)included in this embodiment may extended to support vehicle 100 whengyro stabilization units 260 a & b are unable to maintain vehiclestability at a stop—either due to gyro stabilization unit failure or dueto a normally ordered shutdown in order to conserve power. Landing gear500 includes base portion 510 which is coupled to vehicle frame 110 andmakes contact with the ground, and extender mechanism 520 which rotatesbase portion 510 out to deploy and retracts base portion 510 whenvehicle 100 is utilize gyro stabilization units 260 a & b. In oneembodiment, landing gear 500 is also deployed automatically when theflywheel rotation speed drops below the minimum speed required tomaintain stability for vehicle 100 or when vehicle sensors indicate thegyro stabilization units 260 a & b are failing to maintain vehiclestability, and vehicle 100 is stopped. First and second flywheels 270 a& b may be maintained rotating at minimum idle speed in order tominimize startup time, or they are permitted to coast to a stop withmotor-generators 280 a & b in the generator mode in order to harvest anyremaining energy into battery bank 420.

Upon startup again, flywheel motor-generators 280 a & b may be switchedto the motor mode, and power storage unit 410 may provide power toflywheel motor-generators 280 a & b to spin up “hover speed”. By way ofexample, in this embodiment the hover speed is approximately 10,000 rpmfor standard loading conditions with a single occupant. With first andsecond flywheels 270 a & b at hover speed, system controller 440 mayraise the landing gear 500 and vehicle 100 will remain stable. Systemcontroller 440 will cause gyro stabilization units 260 a & b to precessfirst and second flywheels 270 a & b about their gimbals 290 a & b tocompensate for imbalanced static loads and dynamic loads whilemaintaining vehicle 100 upright.

Thus, it is to be understood that, at least in light of the abovedescription and the respective figures, embodiments of the inventiondescribe a system including a drive wheel motor-generator to transferenergy to and from a drive wheel of a vehicle, a flywheelmotor-generator to transfer energy to and from a flywheel included in agyroscope-stabilizer of the vehicle, a capacitor bank including abattery, and a power controller (implemented as, for example, a moduleor logic). Said power controller may transfer energy from the flywheelmotor-generator to the capacitor bank in response to detecting an inputto increase the speed of the vehicle, and transfer energy from the drivewheel motor-generator to the capacitor bank in response to detecting aninput to decrease the speed of the vehicle.

Said power controller may also transfer energy from the capacitor bankto the drive wheel motor-generator in response to detecting the input toincrease the speed of the vehicle, and transfer energy from thecapacitor bank to the flywheel motor-generator in response to detectingthe input to decrease the speed of the vehicle.

Said power controller may also transfer energy not required by thedrive-wheel motor to the capacitor bank or the battery in response todetecting an input to increase the speed of the vehicle, and transferenergy not required by the flywheel to the capacitor bank or the batteryin response to detecting an input to decrease the speed of the vehicle.

Embodiments of the invention further describe, in the event the input todecrease the speed of the vehicle comprises an input to engage a brakingsystem of the vehicle, a braking system that may generate energytransferable from the drive wheel motor-generator.

Embodiments of said power controller may further transfer energy fromthe capacitor bank to the flywheel motor-generator based, at least inpart, on whether the speed of the vehicle will affect stability of thevehicle. For example, the power controller may determine the input toincrease the speed of the vehicle will not affect stability of thevehicle, and transfer energy from the capacitor bank to the flywheelmotor-generator in response to determining the input to increase thespeed of the vehicle will not affect stability of the vehicle.Embodiments of said power controller may further determine that an inputto decrease the speed of the vehicle will affect stability of thevehicle, and transfer energy from the capacitor bank to the flywheelmotor-generator in response to determining the input to decrease thespeed of the vehicle will affect stability of the vehicle.

Embodiments of the invention further describe a flywheel motor-generatorcontrol module (or logic) to control the flywheel of the gyroscope andto operate in a motor mode and a generator mode. The motor modecomprises transferring electrical current to the gyroscope to change theorientation or the rotational speed of the flywheel, and the generatormode comprises transferring electrical current generated by flywheelfrom the gyroscope. A drive wheel motor-generator control module (orlogic) is similarly described, said module to control the front or therear wheel of the vehicle and to operate in a motor mode and a generatormode. The motor mode comprises receiving electrical current to therotational speed of the respective wheel, and the generator modecomprises transferring electrical current generated by the respectivewheel.

Various components referred to above as processes, servers, or toolsdescribed herein may be a means for performing the functions described.Each component described herein includes software or hardware, or acombination of these. The components may be implemented as softwaremodules, hardware modules, special-purpose hardware (e.g., applicationspecific hardware, ASICs, DSPs, etc.), embedded controllers, hardwiredcircuitry, etc.

Software content (e.g., data, instructions, configuration) may beprovided via an article of manufacture including a computer storagereadable medium, which provides content that represents instructionsthat may be executed. The content may result in a computer performingvarious functions/operations described herein. A computer readablestorage medium includes any mechanism that provides (i.e., stores and/ortransmits) information in a form accessible by a computer (e.g.,computing device, electronic system, etc.), such asrecordable/non-recordable media (e.g., read only memory (ROM), randomaccess memory (RAM), magnetic disk storage media, optical storage media,flash memory devices, etc.). The content may be directly executable(“object” or “executable” form), source code, or difference code(“delta” or “patch” code). A computer readable storage medium may alsoinclude a storage or database from which content may be downloaded. Acomputer readable storage medium may also include a device or producthaving content stored thereon at a time of sale or delivery. Thus,delivering a device with stored content, or offering content fordownload over a communication medium may be understood as providing anarticle of manufacture with such content described herein.

Those skilled in the art will recognize that numerous modifications andchanges may be made to the preferred embodiment without departing fromthe scope of the claimed invention. It will, of course, be understoodthat modifications of the invention, in its various aspects, will beapparent to those skilled in the art, some being apparent only afterstudy, others being matters of routine mechanical, chemical andelectronic design. No single feature, function or property of thepreferred embodiment is essential. Other embodiments are possible, theirspecific designs depending upon the particular application. As such, thescope of the invention should not be limited by the particularembodiments herein described but should be defined only by the appendedclaims and equivalents thereof.

Methods and processes, although shown in a particular sequence or order,unless otherwise specified, the order of the actions may be modified.Thus, the methods and processes described above should be understoodonly as examples, and may be performed in a different order, and someactions may be performed in parallel. Additionally, one or more actionsmay be omitted in various embodiments of the invention; thus, not allactions are required in every implementation. Other process flows arepossible.

1. A system comprising: a processor; a memory; and a control modulestored in the memory and executed via the processor to receive data froma plurality of sensors indicating orientation of a frame of a vehicle,orientation of a front wheel of the vehicle with respect to the frame,orientation and rotational speed of a flywheel included in a gyroscopecoupled to the frame, and speed of the frame, determine a vehicle statebased, at least in part, on the received data, and adjust at least oneof the orientation and rotational speed of the flywheel based, at leastin part, on the vehicle state.
 2. The system of claim 1, the controlmodule to further receive input to change at least one of speed anddirection of the vehicle, and adjust at least one of the orientation androtational speed of the flywheel further based, at least in part, on theinput to change at least one of speed and direction of the vehicle. 3.The system of claim 2, the control module to further determine anintended vehicle state based, at least in part, on the received input,and adjust at least one of the orientation and rotational speed of theflywheel based, at least in part, on the intended vehicle state.
 4. Thesystem of claim 3, wherein the received input comprises a command toturn the front wheel, the intended vehicle state to comprise a turn, thecontrol module to adjust the orientation and rotational speed of theflywheel to maintain stability during the turn.
 5. The system of 1further comprising: a flywheel motor-generator control module to controlthe flywheel of the gyroscope and to operate in a motor mode and agenerator mode, wherein the motor mode comprises transferring electricalcurrent to the gyroscope to change at least one of the orientation androtational speed of the flywheel, and the generator mode comprisestransferring electrical current generated by flywheel from thegyroscope.
 6. The system of claim 1, further comprising a drive wheelmotor-generator control module to control at least one of the front andrear wheel of the vehicle and to operate in a motor mode and a generatormode, wherein the motor mode comprises receiving electrical current tothe rotational speed of the respective wheel, and generator modecomprises transferring electrical current generated by the respectivewheel.
 7. An article of manufacture comprising a machine accessiblestorage medium having content to provide instructions to result in amachine performing operations including: receiving data from a pluralityof sensors indicating orientation of a frame of a vehicle, orientationof a front wheel of the vehicle with respect to the frame, orientationand rotational speed of a flywheel included in a gyroscope coupled tothe frame, and speed of frame; determining a vehicle state based, atleast in part, on the received data; and adjusting at least one of theorientation and rotational speed of the flywheel based, at least inpart, on data from the plurality of sensors and input to change at leastone of speed and direction of the vehicle.
 8. The article of manufactureof claim 7, the operations further including: receiving input to changeat least one of speed and direction of the vehicle; and adjusting atleast one of the orientation and rotational speed of the flywheelfurther based, at least in part, on the input to change at least one ofspeed and direction of the vehicle.
 9. The article of manufacture ofclaim 8, the operations further including: determining an intendedvehicle state based, at least in part, on the received input; andadjusting at least one of the orientation and rotational speed of theflywheel based, at least in part, on the intended vehicle state.
 10. Thearticle of manufacture of claim 9, wherein the received input comprisesa command to turn the front wheel, the intended vehicle state tocomprise a turn, the operations further including adjusting theorientation and rotational speed of the flywheel to maintain stabilityduring the turn.
 11. The article of manufacture of claim 7, theoperations further including: controlling the flywheel of the gyroscopeto operate in a motor mode and a generator mode, wherein the motor modecomprises transferring electrical current to the gyroscope to change atleast one of the orientation and rotational speed of the flywheel, andthe generator mode comprises transferring electrical current generatedby flywheel from the gyroscope.
 12. The article of manufacture of claim7, the operations further including: controlling at least one of thefront and rear wheel of the vehicle to operate in a motor mode and agenerator mode, wherein the motor mode comprises receiving electricalcurrent to the rotational speed of the respective wheel, and generatormode comprises transferring electrical current generated by therespective wheel.
 13. A method comprising: receiving data from aplurality of sensors indicating orientation of a frame of a vehicle,orientation of a front wheel of the vehicle with respect to the frame,orientation and rotational speed of a flywheel included in a gyroscopecoupled to the frame, and speed of frame; determining a vehicle statebased, at least in part, on the received data; and adjusting at leastone of the orientation and rotational speed of the flywheel based, atleast in part, on data from the plurality of sensors and input to changeat least one of speed and direction of the vehicle.
 14. The method ofclaim 13, further comprising: receiving input to change at least one ofspeed and direction of the vehicle; and adjusting at least one of theorientation and rotational speed of the flywheel further based, at leastin part, on the input to change at least one of speed and direction ofthe vehicle.
 15. The method of claim 14, further comprising: determiningan intended vehicle state based, at least in part, on the receivedinput; and adjusting at least one of the orientation and rotationalspeed of the flywheel based, at least in part, on the intended vehiclestate.
 16. The method of claim 15, wherein the received input comprisesa command to turn the front wheel, the intended vehicle state tocomprise a turn, the method further comprising: adjusting theorientation and rotational speed of the flywheel to maintain stabilityduring the turn.
 17. The method of claim 13, further comprising:controlling the flywheel of the gyroscope to operate in a motor mode anda generator mode, wherein the motor mode comprises transferringelectrical current to the gyroscope to change at least one of theorientation and rotational speed of the flywheel, and the generator modecomprises transferring electrical current generated by flywheel from thegyroscope.
 18. The method of claim 13, further comprising: controllingat least one of the front and rear wheel of the vehicle to operate in amotor mode and a generator mode, wherein the motor mode comprisesreceiving electrical current to the rotational speed of the respectivewheel, and generator mode comprises transferring electrical currentgenerated by the respective wheel.